High fog dominated the weather today over large parts of the northern side of the Alps! The thickness of the cold air lake close to the ground actually increased last night! As a result, the upper limit of the high fog rose to 1600 to 1800 meters. During the course of the day! it partially cleared up on the northern side of the Alps, but in the other areas! it was not affected by the March sun.
High fog covers the Jura.
Animation of the webcam image on La Dôle last nigh! Since the inversion was almost exactly at the height of the ridge, the high fog! was pushed westward by the bise just above the Jura and temporarily formed a standing wave in the lee! (Source: Roundshot MeteoSwiss)
The high fog clearing seen from above
Webcam image of the Pizol ski area looking north. While the high fog dominated here in the morning, it had partially cleared up by midday. (Source: Fotowebcam.eu)
Resolution yes or no?
The forecast of the high fog clearing is always a challenge for man and machine. The numerical weather models predicted an almost complete clearing of the high fog, which did not turn out to be the case, as the following graphics show. The forecasters were more cautious and spoke in the weather report of “extensive high fog and clearing in the afternoon”, but no one really believed that it would clear up.
Comparison of the forecast of low cloud cover (in red) according to slovenia phone number library the COSMO-1E model (left) and reality (right), shown using satellite images and station measurements of sunshine duration (in red, last 10 minutes). One can see the only slight change in the high fog cover in reality, compared to the model, where the high fog almost completely dissipates.
Comparison of the forecast of low cloud cover (in red) according to the COSMO-1E model (left) and reality (right), shown using satellite images and station measurements of sunshine duration (in red, last 10 minutes). You can see the only slight change in the high fog cover in reality, compared to the model, where the high fog almost completely dissipates. (Source: MeteoSwiss and EuMetSat)
The higher the fog the lower the chances of dissolution
So let’s take a look at the high fog statistics. This shows that the higher why do broken links appear on the site? the upper limit of the high fog, the less likely it is that it will dissolve. The connection is clear: when the upper limit of the high fog is high, the cold air lake near alb directory the ground is more powerful, and more (solar) energy is needed to warm it up. Conversely, less energy is needed for a shallower high fog. Weather models often show a high fog upper limit that is too low, which would encourage a faster dissolution.
When we talk about solar energy, we already come to the second connection: the higher the sun is and the longer the day, the more solar energy is available to dissolve the high fog. This explains the curve in the next graphic. This shows the probability of a persistent high fog cover depending on the time of year and the height of the upper limit of the high fog.
